1. Field of the Invention
The present invention relates to a pattern recognition apparatus, and more specifically to a general pattern recognition apparatus which can be applied to extract the characteristics from not only input images such as figures and letters but also other various matters changing in a time series.
2. Description of Related Art
At present, so-called pattern recognition apparatuses are widely used in an industrial field, for example as apparatuses for reading letters and systems for sorting components. The feature of recognition method common to the conventional apparatuses is to firstly extract various characteristics, which are commonly contained in a group of objects to be recognized, from the input pattern data, and then to categorize on the basis of the extracted characteristics.
The processing part of such recognition apparatuses comprises a digital processor and a special circuit which quantitatively extracts specific characteristics, such as a high speed Fourier transformation circuit. The program for the digital processor can be designed according to the objects for recognition. Such a recognition apparatus is specialized to meet the very first industrial demand for a high-speed recognition.
On the other hand, the specialization of the recognition apparatus makes it necessary to design an apparatus and a program for each recognition object category. As a result, the related techniques are more specialized, and design and modifications works have become more complicated. Furthermore, the complication of category classification processing lowers the reliability of recognition results, resulting in more difficult quality control of products manufactured in the production system using the pattern recognition system.
On the viewpoint of the manufacturer's side, this follows that a high degree of design work is required for each of specifications of orders received, and that the cost of the product including training of engineers becomes higher.
On the viewpoint of the user's side, there exist disadvantages on the technical point and the cost of use such that the technical information on the recognition objects themselves which the user wants to maintain confidential can flow out to the maker's side, and the user is forced to frequently change the apparatus to a new model with improved function.
As above-described, the pattern recognition apparatus has encountered with disadvantages of the specialization and complication.